فهرست مطالب فاطمه هادی پور

This research examines the elastic property as one of the mechanical properties and antibacterial properties of cellulose nanoparticles and rosemary plant extract and their effect on the overall performance of epoxy biocomposites based on cellulose nanoparticle and rosemary extract. In this article, rosemary plant is used to determine the antimicrobial activity. At first, the samples were made for uniform distribution with four weight percents (pure, 0.5%, 1%, 1.5%, 2%) of rosemary extract, nano cellulose and the combination of extract and nano cellulose.Then the samples were subjected to tensile test and the results indicate that the Young's modulus started to increase from 0.5% by weight and the highest Young's modulus is obtained at 1.5% by weight of the reinforcements. Also, the mechanical properties of the samples started to decrease at 2% by weight, which can be due to the clumping or agglomeration of non-reinforcers in the epoxy, which reduces its mechanical properties. In the antibacterial test, based on the results, Escherichia coli bacteria did not show sensitivity to rosemary extract and no lack of growth was observed. This is while Staphylococcus aureus bacteria showed sensitivity to rosemary extract and recorded a 20 mm diameter halo. Finally, Staphylococcus bacteria is sensitive to the manufactured biocomposites and the best antibacterial performance was observed in the hybrid biocomposite at 2% by weight.

The aim of this study was to test a structural model of metacognitive beliefs with mindfulness of students with social phobia by taking the mediating role of anxiety sensitivity into consideration.

This research was a correlational study in the form of a structural equation modeling design. The Statistical population of the study consisted of all the female undergraduate students of Najafabad Azad University who had taken academic courses in 2019-2020. Among them, 500 students who were willing to participate were selected through convenient sampling method. They were then asked to complete four questionnaires of Social Phobia Inventory (SPIN: Connor et al, 2000), Metacognition Questionnaire (MCQ: Wells & Cartwright-Hatton, 2004); the short form of Freiburg Mindfulness Inventory (FMI: Walach et al, 2006), and Anxiety Sensitivity Index (ASI: Floyd et al., 2005). The data were analyzed using structural equation modeling by Amos software.

The results showed that the structural model of metacognitive beliefs with mindfulness of students with social phobia through the mediating role of anxiety sensitivity fits the emprical data. The direct effect of metacognitive beliefs on mindfulness and anxiety sensitivity, and the direct effect of anxiety sensitivity on standard mindfulness are significant. The indirect standard effect of metacognitive beliefs on mindfulness of students with social phobia through anxiety sensitivity is also significant.